Does every FD3S need V-mount?
 

That air box needs to go, and need an air guide for your SMIC Cool Charge Intercooler Duct , easiest to find a stock intake, or an auto-exe/knighsports intake that does not pull air from the radiator. Seen that ARC air box blow more engines than I can count in the 90's.

Properly ducted SMIC is best of you have/want a stock hood.
V-Mount is best if you have a properly ducted vented hood(not just a random vented hood, a proper vent customized specifically for your setup).

FMIC is a bad choice IMO, lots of anecdotal "success" stories with them but bottom line it is still distant second place to v-mount if you are going to mod your car that drastically.

You can keep the current intercooler, however you will REALLY want/need to get ducting for it. That top metal guide is not going to be enough. With the IC the way it is right now you are going to essentially guarantee that you'll heat soak the IC by constantly blowing hot air from the radiator directly into your intercooler. You can modify a stock IC duct to fit with the GReddy SMIC, it won't be pretty but it will be better than what you have currently.

If you keep your power goals in check than you should be fine with a well ducted SMIC. I would also recommend running a simple water/meth injection system, it doesn't need to be fancy just something that is pressure activated about 2psi under your max boost will be fine.

Also, you said that you shift the FD at 2k - 2.5krpms... DO NOT DO THIS!!!! Carbon buildup is a real problem with these cars in stock form due to how the rotary needs oil to be injected into the combustion chamber for lubrication. Running the car to redline under load (do not just free-rev it) is actually very healthy for the motor since it helps burn off carbon deposits. If you constantly shift in low rpms than you'll be forever building up carbon deposits, but never burning them off. Doing a water injection system will actually help, significantly, with reducing or completely removing carbon deposits. On the other hand, you can periodically "Steam Clean" your engine internals by doing something like mentioned here: Emissions Removal (it is entirely safe, I used to do it to my own car every 6 months or so before I got a water injection kit installed).

I think a V-mount is the ideal setup, regardless of hood, climate, other mods. The original stock set up was an odd compromise after you see the v-mount design, and all SMIC upgrades were effectively improvements on a fundamentally flawed design.

Your I/C size is fine for your current needs, but it looks like you are missing some ducting in front of it as I can see you radiator fans in your second picture. You should fix that. Should be cheap and easy.

You also need to get COLD air to your intake air filters. You are currently sucking in HOT air from the engine bay.

It looks like you can add the stock airbox duct to your current setup. But if that is not an option then you should get something else that is ducted like the M2 or Pettit intake kits.

Or if you want to go really balling:

https://www.rx7club.com/3rd-generati...ntake-1125228/


Tom

^^^ Very good advice.

I did something similar to this on one of my previous FD's, it supported just over 300 RWHP with the ARC SMIC, which is smaller than the one the OP has.

Proper ducting + a splash of water wetter + Koyo Triple pass + OP's set up with the Greddy/ARC combo = If you're overheating there's a bigger problem.

I've run a similar set up for years in the summertime California desert heat with no problems ever. I have a Blitz SMIC and a cheap bastard airbox, but other than that, our cars are set up closely. A good radiator, proper ducting, a splash of Water Wetter and maybe a lower temp thermostat should be all you need.

Thermostat 180° F

FC thermoswitch is another little trick
https://www.rx7club.com/3rd-gen-arch...tch-fd-447606/

https://www.rx7club.com/auxiliary-injection-173/

Check out the Aux Injection sub forum for more information.

I have an Autoexe Intake... If you are interested drop me a pm!

Koyo seems to cool a little better but Fluidyne fits better and is still an upgrade from stock. Ron Davis/AWR are expensive but nice. Stock fans are hard to beat. Keep em.

I bought a three-pass Koyo and made it fit with my dual oil coolers (another great cooling upgrade to think about: dual oil coolers from an R1 or R2 model), sway bar brace and A/C condenser. You might have to use some patience to make it all fit, but it will.

The stock fans are good, but the RX8 fans, the version with the four wires, that match the RX 7 wires are better. They draw less current, are quieter, and the RX8 blades move more air. Simply rewire using the stock plugs from the RX7 fans and reuse the stock RX7 fan shroud. The RX8 fans and blades fit perfectly with no modifications needed. Just color match all four wires. The RX8 motors brand new from Mazda are $55 each with typical 30% discount. Can get used fan blades from RX8 at junk yard or on Ebay usually or get new from Mazda for around $100 each. Cheaper to get used blades. I repainted my stock RX7 plastic shroud with Eastwood plastic trim reconditioner paint and painted the new motors black with caliper paint. Looks brand new and works great.

do you have a write up on this lol

I went through it fairly recently. The stock fans work really well. The aesthetics of the new ones are nice.

https://www.rx7club.com/3rd-generati...x7-fd-1085155/
https://www.rx7club.com/3rd-generati...ource-1091859/
https://www.rx7club.com/3rd-generati...-fans-1078526/
https://www.rx7club.com/build-thread...1084988/page3/